The University of British Columbia

The authors describe a methodological framework for the analysis of network congestion in a generic asynchronous transfer mode (ATM)/broadband-ISDN (B-ISDN) network. A three-level hierarchical network congestion management architecture is proposed; with a higher hierarchical level corresponding to a slower congestion control frequency. By dividing the congestion problem into scopes according to the control frequencies, the architecture incorporates isolated, distributed, and centralized control models into the corresponding congestion scopes and then applies appropriate control schemes. Within this architectural framework, the authors focus on the hierarchical congestion management schemes at the UNI (user-network interface) access node which allows an integrated access of heterogeneous user traffic types; and which allows its output links to the network to be subjected to random disruptions due to internode congestion control exerted by the immediate neighboring network nodes